coverity: fix uninit variable issue in driver

Related CID:
389832, 389838, 389880, 286743, 286752, 395156, 291011, 396001, 396002

components/esp_gdbstub/src/packet.c

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <assert.h>
 #include "esp_gdbstub_common.h"
 
 // GDB command input buffer
@@ -45,6 +46,8 @@ void esp_gdbstub_send_str(const char *c)
 // 'bits'/4 dictates the number of hex chars sent.
 void esp_gdbstub_send_hex(int val, int bits)
 {
+    // sanity check, in case the following (i - 4) is a negative value
+    assert(bits >= 4);
     const char *hex_chars = "0123456789abcdef";
     for (int i = bits; i > 0; i -= 4) {
         esp_gdbstub_send_char(hex_chars[(val >> (i - 4)) & 0xf]);

components/esp_hw_support/port/esp32h2/systimer.c

@@ -7,8 +7,8 @@
 #include "esp_private/systimer.h"
 
 /**
- * @brief systimer's clock source is fixed to XTAL (40MHz), and has a fixed fractional divider (2.5).
- *        So the resolution of the systimer is 40MHz/2.5 = 16MHz.
+ * @brief systimer's clock source is fixed to XTAL (32MHz), and has a fixed fractional divider (2.0).
+ *        So the resolution of the systimer is 32MHz/2.0 = 16MHz.
  */
 
 uint64_t systimer_ticks_to_us(uint64_t ticks)

components/esp_hw_support/rtc_wdt.c

@@ -78,7 +78,7 @@ static uint32_t get_addr_reg(rtc_wdt_stage_t stage)
     } else if (stage == RTC_WDT_STAGE2) {
         reg = RTC_CNTL_WDTCONFIG3_REG;
     } else {
-    	reg = RTC_CNTL_WDTCONFIG4_REG;
+        reg = RTC_CNTL_WDTCONFIG4_REG;
     }
     return reg;
 }
@@ -98,14 +98,18 @@ esp_err_t rtc_wdt_set_time(rtc_wdt_stage_t stage, unsigned int timeout_ms)
     return ESP_OK;
 }
 
-esp_err_t rtc_wdt_get_timeout(rtc_wdt_stage_t stage, unsigned int* timeout_ms)
+esp_err_t rtc_wdt_get_timeout(rtc_wdt_stage_t stage, unsigned int *timeout_ms)
 {
     if (stage > 3) {
         return ESP_ERR_INVALID_ARG;
     }
     uint32_t time_tick;
+    uint32_t rtc_slow_freq = rtc_clk_slow_freq_get_hz();
+    if (rtc_slow_freq == 0) {
+        return ESP_ERR_INVALID_STATE;
+    }
     time_tick = READ_PERI_REG(get_addr_reg(stage));
-    *timeout_ms = time_tick * 1000 / rtc_clk_slow_freq_get_hz();
+    *timeout_ms = time_tick * 1000 / rtc_slow_freq;
 
     return ESP_OK;
 }

components/esp_ringbuf/ringbuf.c

@@ -782,7 +782,7 @@ static BaseType_t prvReceiveGeneric(Ringbuffer_t *pxRingbuffer,
         portENTER_CRITICAL(&pxRingbuffer->mux);
         if (prvCheckItemAvail(pxRingbuffer) == pdTRUE) {
             //Item is available for retrieval
-            BaseType_t xIsSplit;
+            BaseType_t xIsSplit = pdFALSE;
             if (pxRingbuffer->uxRingbufferFlags & rbBYTE_BUFFER_FLAG) {
                 //Second argument (pxIsSplit) is unused for byte buffers
                 *pvItem1 = pxRingbuffer->pvGetItem(pxRingbuffer, NULL, xMaxSize, xItemSize1);
@@ -836,7 +836,7 @@ static BaseType_t prvReceiveGenericFromISR(Ringbuffer_t *pxRingbuffer,
 
     portENTER_CRITICAL_ISR(&pxRingbuffer->mux);
     if(prvCheckItemAvail(pxRingbuffer) == pdTRUE) {
-        BaseType_t xIsSplit;
+        BaseType_t xIsSplit = pdFALSE;
         if (pxRingbuffer->uxRingbufferFlags & rbBYTE_BUFFER_FLAG) {
             //Second argument (pxIsSplit) is unused for byte buffers
             *pvItem1 = pxRingbuffer->pvGetItem(pxRingbuffer, NULL, xMaxSize, xItemSize1);

components/esp_serial_slave_link/essl_sdio.c

@@ -133,7 +133,7 @@ esp_err_t essl_sdio_init(void *arg, uint32_t wait_ms)
 {
     essl_sdio_context_t* ctx = arg;
     esp_err_t err;
-    uint8_t ioe;
+    uint8_t ioe = 0;
     sdmmc_card_t* card = ctx->card;
 
     err = sdmmc_io_read_byte(card, 0, SD_IO_CCCR_FN_ENABLE, &ioe);
@@ -159,7 +159,7 @@ esp_err_t essl_sdio_init(void *arg, uint32_t wait_ms)
     }
 
     // get interrupt status
-    uint8_t ie;
+    uint8_t ie = 0;
     err = sdmmc_io_read_byte(card, 0, SD_IO_CCCR_INT_ENABLE, &ie);
     if (err != ESP_OK) return err;
     ESP_LOGD(TAG,"IE: 0x%02x", ie);
@@ -171,7 +171,7 @@ esp_err_t essl_sdio_init(void *arg, uint32_t wait_ms)
     ESP_LOGD(TAG, "IE: 0x%02x", ie);
 
     // get bus width register
-    uint8_t bus_width;
+    uint8_t bus_width = 0;
     err = sdmmc_io_read_byte(card, 0, SD_IO_CCCR_BUS_WIDTH, &bus_width);
     if (err != ESP_OK) return err;
     ESP_LOGD(TAG,"BUS_WIDTH: 0x%02x", bus_width);